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Pyruvate Dehydrogenase Kinase Protects Dopaminergic Neurons from Oxidative Stress in Drosophila DJ-1 Null Mutants

  • Lee, Yoonjeong;Kim, Jaehyeon;Kim, Hyunjin;Han, Ji Eun;Kim, Sohee;Kang, Kyong-hwa;Kim, Donghoon;Kim, Jong-Min;Koh, Hyongjong
    • Molecules and Cells
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    • 제45권7호
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    • pp.454-464
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    • 2022
  • DJ-1 is one of the causative genes of early-onset familial Parkinson's disease (PD). As a result, DJ-1 influences the pathogenesis of sporadic PD. DJ-1 has various physiological functions that converge to control the levels of intracellular reactive oxygen species (ROS). Based on genetic analyses that sought to investigate novel antioxidant DJ-1 downstream genes, pyruvate dehydrogenase (PDH) kinase (PDK) was demonstrated to increase survival rates and decrease dopaminergic (DA) neuron loss in DJ-1 mutant flies under oxidative stress. PDK phosphorylates and inhibits the PDH complex (PDC), subsequently downregulating glucose metabolism in the mitochondria, which is a major source of intracellular ROS. A loss-of-function mutation in PDK was not found to have a significant effect on fly development and reproduction, but severely ameliorated oxidative stress resistance. Thus, PDK plays a critical role in the protection against oxidative stress. Loss of PDH phosphatase (PDP), which dephosphorylates and activates PDH, was also shown to protect DJ-1 mutants from oxidative stress, ultimately supporting our findings. Further genetic analyses suggested that DJ-1 controls PDK expression through hypoxia-inducible factor 1 (HIF-1), a transcriptional regulator of the adaptive response to hypoxia and oxidative stress. Furthermore, CPI-613, an inhibitor of PDH, protected DJ-1 null flies from oxidative stress, suggesting that the genetic and pharmacological inhibition of PDH may be a novel treatment strategy for PD associated with DJ-1 dysfunction.

이중에너지 컴퓨터 단층촬영을 통해 진단된 폐의 미세혈관종양색전증 (Microvascular Pulmonary Tumor Embolism Detected by Perfusion Images of Dual-Energy Computed Tomography)

  • 옥태진;조민수;장선주;박한승;박환성;박세정;윤신교;이호수;백충희;김광운;김달용;홍윤기;서준범;오연목
    • Tuberculosis and Respiratory Diseases
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    • 제72권1호
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    • pp.63-67
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    • 2012
  • Although advances in multi-detector computed tomography (CT) technique make it possible to evaluate peripheral subsegmental pulmonary arteries, several studies have reported that small peripheral embolisms may still be missed. Recently, some reports demonstrated that dual-energy CT improved the capability to detect peripheral pulmonary embolism. We report a case of lymphoma presenting as disseminated microvascular pulmonary tumor embolism, detected by perfusion images using dual energy CT.

Panax Ginseng inhibited HIF-1a activation and inflammatory cytokine in HMC-1 cells activated by phorbol myristate acetate and A23187

  • Choi, In-Young;Jeong, Hyun-Ja;An, Hyo-Jin;Kang, Tae-Hee;Zo, Chul-Won;Song, Bong-Keun;Park, Eun-Jeong;Kim, Eun-Cheol;Um, Jae-Young;Kim, Hyung-Min;Hong, Seung-Heon
    • Advances in Traditional Medicine
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    • 제8권4호
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    • pp.440-447
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    • 2008
  • This study investigated the role of Panax ginseng (PG) on the phorbol myristate acetate (PMA) + calcium ionophore A23187-induced hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$) activation, phosphorylation of the extracellular signal-regulated kinase (ERK), and inflammatory cytokine production from the human mast cell line, HMC-1. HIF-$1{\alpha}$ and phosphorylation of ERK were observed by Western blotting. The inflammatory cytokine production was determined by enzyme-linked immunosorbent assay. PG inhibited the PMA+A23187-induced HIF-$1{\alpha}$ expression and the subsequent production of vascular endothelial growth factor. In addition, PG suppressed PMA + A23187-induced phosphorylation of ERK. We also show that the increased cytokines interleukin (IL)-$1{\beta}$, IL-6, and tumour necrosis factor-${\alpha}$ level was significantly inhibited by treatment of PG. In the present study, we report for the first time that PG is an inhibitor of HIF-$1{\alpha}$ and cytokines on the mast cell-mediated inflammatory responses.

[ $\beta$ ]-Secretase (BACE1) Inhibitors from Sanguisorbae Radix

  • Lee, Hee-Ju;Seong, Yeon-Hee;Bae, Ki-Hwan;Kwon, Soon-Ho;Kwak, Hye-Min;Nho, Si-Kab;Kim, Kyung-A;Hur, Jong-Moon;Lee, Kyung-Bok;Kang, Young-Hwa;Song, Kyung-Sik
    • Archives of Pharmacal Research
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    • 제28권7호
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    • pp.799-803
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    • 2005
  • In the course of screening anti-dementia agents from natural products, two $\beta$-secretase (BACE1) inhibitors were isolated from the ethyl acetate soluble fraction of Sanguisorbae Radix by the activity-guided purification using silica gel, Sephadex LH-20, and RP-HPLC. They were identified as 1,2,3-trigalloyl-4,6-hexahydroxydiphenoyl-$\beta$-D-glucopyranoside (Tellimagrandin II, 1) and 1,2,3,4,6-pentagalloyl-$\beta$-D-glucopyranoside (2) and were shown to non-competitively inhibit $\beta$-secretase (BACE1) with the $IC_{50}$ values of $3.10{\times}10^{-6}M\;and\;3.76{\times}10^{-6}M$, respectively. The Ki values of 1 and 2 were $6.84{\times}10^{-6}M\;and\;5.13{\times}10^{-6}M$. They were less inhibitory to asecretase (TACE) and other serine proteases such as chymotrypsin, trypsin, and elastase, suggesting that they were relatively specific inhibitors of BACE1.

SARS-CoV-2 Infection Induces HMGB1 Secretion Through Post-Translational Modification and PANoptosis

  • Man Sup Kwak;Seoyeon Choi;Jiseon Kim;Hoojung Lee;In Ho Park;Jooyeon Oh;Duong Ngoc Mai;Nam-Hyuk Cho;Ki Taek Nam;Jeon-Soo Shin
    • IMMUNE NETWORK
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    • 제23권3호
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    • pp.25.1-25.17
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    • 2023
  • Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection induces excessive pro-inflammatory cytokine release and cell death, leading to organ damage and mortality. High-mobility group box 1 (HMGB1) is one of the damage-associated molecular patterns that can be secreted by pro-inflammatory stimuli, including viral infections, and its excessive secretion levels are related to a variety of inflammatory diseases. Here, the aim of the study was to show that SARS-CoV-2 infection induced HMGB1 secretion via active and passive release. Active HMGB1 secretion was mediated by post-translational modifications, such as acetylation, phosphorylation, and oxidation in HEK293E/ACE2-C-GFP and Calu-3 cells during SARS-CoV-2 infection. Passive release of HMGB1 has been linked to various types of cell death; however, we demonstrated for the first time that PANoptosis, which integrates other cell death pathways, including pyroptosis, apoptosis, and necroptosis, is related to passive HMGB1 release during SARS-CoV-2 infection. In addition, cytoplasmic translocation and extracellular secretion or release of HMGB1 were confirmed via immunohistochemistry and immunofluorescence in the lung tissues of humans and angiotensin-converting enzyme 2-overexpressing mice infected with SARS-CoV-2.

D-1,3-Dioxolane 및 D-1,3-Oxathiolane 피리미딘 뉴크레오사이드의 합성 (Synthesis of D-1,3-Dioxolane and D-1,3-Oxathiolane Pyrimidine Nucleosides)

  • 홍준희;차마리;신성은;최보길;정병호;김중협;이종교;정원근;천문우
    • 약학회지
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    • 제38권6호
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    • pp.703-711
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    • 1994
  • We synthesized D-1,3-dioxolanyl acetate from D-mannose using Frazer-Reide reaction and D-1,3-oxathiolanyl acetate from either D-mannose or D-galactose in good yields. These acetates were conjugated with various disilylated pyrimidine base using trimethylsilyl trifluoromethane sulfonate as a Lewis acid catalyst to obtain 32 different D-nucleosides.

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